Two Worlds Collide
by WarriorOfHades
Summary: Zues is worried. Shadowhunters and demigods are about to collide and a new danger looms on the horizon. So Zues decides to make a dangerous decision. He releases Katherine di Luminoso from her punishment. The teenage girl is a known cut throat, dangerous, powerful, and extremely loyal to her father Hades and her siblings. Her involvement could save them... or destroy them.
1. Chapter 1

Of Shadows

Three people stood in the throne room of Hades palace. Zues and Hades were arguing yet again over the same topic, just as they had every decade. The object of their argument stood apart from the gods with a bored look on her face,staring at them the way a mother would when her children were arguing over a broken toy. She'd heard the argument repeated so many times she could say it word for word.

" Brother please! Has she not been punished enough? You have forbidden her from being known by mortals, taken the sunlight from her life, and sent her to Tartarus three times! Three Brother! The fact she still has her sanity is a miracle!" pleaded Hades.

"She deserves her punishment! She fought for the wrong side in WWII and massacred my children! Why does she deserve light or even sanity." raged Zues.

"She fought for her father just as your children did for you. She did not 'massacre' your children, they were armed and she beat them. You are simply upset that she beat your entire army single-handedly after that filthy trick your son used to kill ALL my children while they were unarmed!" shouted Hades in equal anger.

"Yes my son. My favorite son who she hunted down like a deer. It was not his fault her sister ate the poison instead of her."

"Her sister was six years old. No more than a child!"

"That does not matter Brother! It was war!"

The girl had had enough of this pointless bickering. That war had ended almost 70 years ago. Then the conversation took an interesting turn.

"If I agree to release her from her punishment, then she must agree to give up her immortality." says Zues with finality. Silence befalls the room.

" Katherine? Do you consent to this...agreement?" asks Hades, stunned. The girl nods. She never showed it but she was tired of hiding.

"Yes, Father, I accept."


	2. Chapter 2

Jace's dream was a standard nightmare. It always was. He was currently watching as a horde of demons attacked Clary. It was tearing her apart and he was helpless to stop it, unable to move, to help, to save her. He wanted her to be dead, for her pain to end but he knew she wasn't. One of the ugly brutes turned to him with fearsome yellow lunged at him, he closed his eyes knowing he was about to die. Then his dream suddenly changed, melting away and leaving him in an empty feild of mist. His eyes, now open, scanned his surroundings. A dark, misty figure approached him. He immeadiatley reached for a weapon before realizing that ,duh, he was in a dream. He didn't have any weapons. A few feet away the mist solidified into a girl dressed all in black.

She was both beautiful and terrible at the same time. Her hair was as black as pine pitch and was somwhere between a curl and a wave as it fell down her back. Her skin was so pale it was almost white and it was as smooth as porcelin. She was about five foot and damn was she curvy! But her eyes terrified him. The irises were black, not brown, black. They were so cold when she looked at him that he expected to be turned to ice. They were the eyes of someone who killed and didn't regret it. Who would just as soon kill him as spare him. He was so scared of her, he asked the most basic of all questions.

"W-who are you?"

She looked amused. She wasn't exactly smiling. You know the look on the emporer's face when he's watching gladiator battles? That was her. She cocked her head to the side and studied him, like an animal about to be gutted. She didn't speak for a long while. When she did her voice was cold and sharp. It scared him even though there was no menace in it.

"That is a dangerous question. I'm not going to answer it just yet. Hmmm...no not yet. You see, that would ruin my plan."

"What plan?" he asks.

"All in good time. Tomorrow at noon, you will go to the Starbucks that your sister Isabelle is so fond of. You'll see a boy with golden hair and sky blue eyes with a boy who looks like me. Speak with them. You may find something of interest. I suggest going armed. Get the name of the dark haired boy. I will speak with you then."

"Why should I trust you? Who are you anyway? This sounds like a trap to me."

"You'll go. Your curiosity will force you to. Many lives are counting on you, lives that could be saved by this meeting alone. I will not deny that this wil be dangerous. But it is time."

"Time? Time for what?"

"Time for the secrets of your world to be revealed." her form was fading. " You will be given more information in time. Now, WAKE!"

Jace woke in a cold sweat, panting. He lay back down knowing that no matter how hard he tried, sleep would not come.


	3. Chapter 3

Author's Note: Hey people! WarriorOfHades here! Chapter Three is ready to go. I strongly believe in Solangelo and Malec. They are my OTPs. You don't like it don't read my work. Everyone Is also asking for Thalico. I never believed in Thalico. Nico is gay people! Also Thalia is Lieutenant of the Hunt. Which means NO DATING. Damn, just imagine Artemis's face...

Will threw open the door of Cabin 13 letting sunlight stream in. He marched straight over to the mound of blankets that was his new boyfriend and fell right on top of him.

Bad idea.

Before Will knew what was happening his head hit the floor. Nico had somehow managed to flip them onto the floor, straddle Will, pin his hands over his head, and put a knife against his throat. How could he have forgotten that Nico slept with a knife under his pillow? When Nico's eyes finally cleared of sleep an amused smirk came over his features. He leaned down and placed a chaste kiss on Will's lips. He pulled away much too soon for Will's taste but when Nico moved the knife as well, Will couldn't actually complain.

"What do you want Will? I was sleeping you know." said Nico. Will was still pinned to the floor and Nico didn't seem to have any inclination to let him up.

"I was going to take you into the city today."said Will mimicking Nico's tone."So get dressed." Nico groaned. Will wriggled out from under Nico and left the cabin, knowing Nico would be dressed and ready when he went back.

Will wandered aimlessly around camp for a while. He was seriously trying to avoid a meeting with Percy and Jason, as they leered at him every time he crossed their line of sight. Reyna was even worse, giving him the If-You-Break-His-Heart-I'll-Break-Your-Face speech every time she saw him. He sat under a tree at the edge of the woods.

"Hey Handsome." said a voice.

Will jumped up, turning his head, trying to find the source of the voice.

"Up here." it said. Will looked up to find Nico sitting in the shadowy branches, his amused smirk firmly in place. Will shook his head. He should have known.

"Get down here."said Will. Nico slid from the branch, dropping fluidly to the ground with cat-like grace. Show off. "Ever since I gave you permission to shadow travel, you never walk anywhere." Will complained.

"Walking is so slow. Why walk when you can just appear?" said Nico. Damn that infuriating smirk. Damn it straight to the fiery pits of Hades. Will opened his mouth to complain again and was stopped abruptly when Nico pushed him against a tree and fit his mouth over Will's. Before Will could pull away to say something they disappeared into shadows.

Author's Note: A little shorter but oh well. Ever just get to the middle of a chapter and suddenly not know what to write? Yeah that's me. It's also why this chapter sucks. The next one should be better but no promises. I might see a squirrel...


	4. Chapter 4

**Author's Note: Bonsoir demons, monsters, demigods, and nephilim! Ok I'm not actually french, but I still know you have to say bonsoir instead on bonjour in the evening. The air conditioner is out at my house so it's hotter than the Phlegethon. That's a greek river thingy... look it up. If I describe it I'll start lecturing. This chapter will be a Malec. Enjoy!**

Jace was acting strangely. No one else noticed, but Alec sure did. And what Alec saw was not Jace. This Jace was jumpy and seemed to be paranoid. His eyes darted restlessly around the room and he started at every unexpected noise. Alec wanted to ask his parabatai what was troubling him, but he doubted that would be a good idea as a sarcastic answer was probably the only one he would get. Still he was troubled by this sudden change. He was so deep in thought about this that Isabelle had to call his name three times before he answered.

"Alec! Hurry up! You were supposed to meet Magnus in fifteen minutes! You're going to be late!"

That snapped him out of his stupor. Magnus was never, ever late. This happened to be a stark contrast to Alec, who was almost always late to everything. He dressed quickly and, with a hurried goodbye to Isabelle and a worried look at Jace, left the Institute.

Magnus was, of course, waiting for him just outside his apartment. Alec noted the fact that Magnus's alluring smile was still in place as he looked Alec over. Damn that warlock and his extreme fashion. Magnus was dressed in tight black leather pants, a bright yellow tank top with the words "Sexy and I Know It" written on it in black sequins, a tight, sky blue leather jacket, and black boots that had gold buckles and way too much heel. Alec, however, was dressed in black jeans, a tight black tee, black combat boots, and a black hoodie. It was all fairly baggy, which made it easy to hide weapons. While Magnus stood there with his glitter, makeup, and spikey hair, Alec felt plain and uninteresting. Before Alec could even get in a greeting Magnus's lips descended on his.

"Hello to you too." said Alec breathlessly once they had parted.(Much too soon in his opinion.)"Now can you tell me where we're going?" he said. Magnus had this strange thing about mystery dates. He adored them.

"Calm down Alexander. We'll get there soon enough. Don't be impatient." He chided. Alec surrendered knowing that Magnus would tell him when he wanted to and not a moment sooner. With a sigh he allowed himself to be led away to only God (and Magnus) knew where.


	5. Chapter 5

**Author's Note: I wasn't actually planning on posting this chapter so soon but I just love you guys SO MUCH! ...Ok maybe I got bored, but that's not the point. Jace will finally be showing some nerves here. And maybe some Malec eavesdropping. I'm planning on letting Katherine come in a little. Just not in person or in a dream. She has a plan after all. Everything must go accordingly...**

Jace was terrified. He hated to admit it, but he was. When he had woken up that morning (completely unaware he had gone to sleep in the first place) there had been a note on his nightstand. On it was instructions and a single name: di Luminoso. He looked over the note again.

 _Jace Herondale,_

 _You will arrive noon sharp at the Starbucks down the street. You will tell no one you were there. You will not explain yourself to anyone. As of now you are my champion Jace. I expect unwavering loyalty. This mission is of the utmost importance and my orders must be carried out exactly. If they are not there will be consequences. I will not lose lives for your ignorance._

 _Respectfully,_

 _General di Luminoso_

General? Oh so know she was a general too. She couldn't just be a dream-invading phycotic warlock. Or even a dream-invading phycotic mundane witch. No, no,no she had to be a war general. And he was her champion? What did that mean? And consequences. He shuddered. He did not like the sound of that. He had no doubt that she was not only real, but extremly dangerous. But never the less he arrived at the Starbucks at noon, not a minute late. He could not ignore the fact that there were possible lives in danger. He took a deep breath.

"di Luminoso." he wispered before taking a seat. A few seats over, the warlock Magnus Bane's eyes widened in utter shock.


	6. Chapter 6

**Author's Note: For the time being there will be a lot of Jace POV but it's kind of necessary. Next chapter will be Magnus and his strange ties to Katherine. A little Solangelo fluff in here maybe? Oh, and some reviews would be great. Let me know what you people like or want to see.**

Jace had no idea what he was waiting on. Well obviously a couple of guys that were possibly dangerous but who were they? Shadowhunters? Demons? Downworlders? They might even be mundanes. After a while a pretty employee walked over to ask him if he wanted anything. She looked nervous and was blushing like mad. He flirted with her for a little while before ordering. His coffee was delivered extremely quick.

After half an hour Jace was getting irritated. She had him arrive at noon sharp under threat of consequences. He saw no one who looked remotely like her. Sure some had dark hair and pale skin but no one had her eyes. The bell rang. He sighed and just as before, turned in his seat to see who was coming in.

And stopped cold.

The guy who walked in was about fifteen and could have passed for his mystery patron's twin. Behind him was his exact opposite. He was blonde and tan and looked like sunshine. Jace caught sight of the dark one's eyes. They were dark, cold, and empty. There was no doubt that this was who he was looking for. Quick as a snake the dark one turned his head and caught his eyes. Jace couldn't move. The golden one said something brow furrowed. In answer the dark one started to walk towards Jace. Jace wanted to run far and fast as he could. The boy's hand was on something at his belt. Jace was literally shaking by the time the boy stopped in front of him.

"What are you doing here." hissed the boy."Are you trying to start a war? You'll get us all killed!" the tanned one stopped behind him.

"Nico?" no answer. "Earth to di Angelo. Hello?"

"We're going." he said. "Listen, you never saw us we never saw you, got it? Forget this meeting ever happened. Believe when I say it could save a lot of lives." He spun around, grabbed Sunshine's hand, and dragged him to the door.

"Nico, do we really-" started Sunshine.

"Yes we do Will." he said. The door closed with a chiming sound, and Jace let out a breath he was not aware he had been holding.

 **Author's Note: I personally hated it when people depict Nico as some blushing idiot. I read it and I'm just like, "We are talking about the same badass son of Hades who went through Tartarus** ** _alone,_** **right? I have never see Nico as some blushing school girl.**


	7. Chapter 7

**Author's Note: Ciao! As promised this chapter will be from Magnus's POV as to how he knows Katherine. I mean come on let's face it Magnus knows everyone. Magnus knows your great step aunt's gold fish Merlin and attended his flushing. And of course my friends had to have their two-cents so Alec will meet Katherine as well. If this chapter is awkward weird and completely awful, I blame them.**

Magnus lay in his bed at home trying to steady his breathing. He was completely and utterly failing. He rolled over and stared at the person next to him and felt his heart rate both trying to increase and decrease at the same time. _Alec Lightwood._ Never before had Magnus met such an amazing mortal. Or such a beautiful one. There was such a look of peace on his pale face that his heart decided to slow down. And then seem to stop completely as he realized what it could mean for Alec if di Luminoso's plan succeeded. There was a 99% chance that war would follow. And where there was war there were Shadowhunters. And where there were Shadowhunters, there was Alec. He could not, _would_ not allow Alec to be killed. Carefully he slid out of bed, dressed and made his way to the living room.

Barely had he sat down on the couch when the shadows darkened and in a flash of black Hellfire, the general herself appeared.

He had met her only once before and was definitely not ready for this meeting. She was dressed in black naturally and in full body armor complete with black heeled boots covered in silver buckles. Her armor, though black, was also etched in silver, her hair tied back in a silver band. He knew that in was not merely silver that adored her armor and no doubt her sword, but Tartarian silver. It was by far the most powerful, deadly, and dangerous metal to obtain. She had somehow gotten it during her punishment time in Tartarus as well as her necklace. He forced himself not to shudder. Around her neck on Tartarian silver, and placed upon her fingers in Tartarian silver rings, were Chaos crystals. Beautiful gems that had helped to create the first forms of life, the first immortals. However they were extremely powerful. It was said in legends that they could be used to create immortals when melded with shadow, and could strip even the mighty Zues from his immortality. She was the Ghost Queen, the Shadow's Assassin, the Savior of Death, the Sky's Bane. Then she spoke, her black eyes didn't exactly soften but she seemed a little less murderous.

"Magnus Bane. It seems my little plan was leaked out. I knew that the golden boy was not very tactical but..." she trailed off and shrugged.

"Your plan? I don't believe that such a plan would be very wise...General." he added on the end. She was very strict about respect.

"That is untrue. You believe my plan is very wise and long overdue. However you fear for him." she gestured to his bedroom door. " There is a reason I chose the golden one Magnus. It was not because I have a special fondness for golden, disrespectful assholes. It was because he was the second best I could get. I wanted Alec but I could not take your love from you. I know how that feels first hand. I would not do such a thing."

He nodded. There were many things that could be said about General di Luminoso. Sure she was a cut throat, ruthless, merciless, and in many accounts, insane murderess. But she valued love and loyalty and honor. The reason she was all the things she was was for her family's survival.

"What of Clary? You would rip Jace away from her?" he asked. He realized his disrespectful tone a little to late. The glare that flashed quickly through her eyes made a shark's cold stare seem like that of an innocent and friendly child.

"There was another reason I chose him." she said and Magnus raised an eyebrow."That insufferable idiot simply refuses to die." she smirked and Magnus laughed. "I almost forgot. I brought this for you." She reached into her armor to draw something out.

And Alec flew out of the bedroom fully dressed, a knife aimed at her throat.

 **Author's Note: Kind of a cliff-hanger. No worries, I'll have the next one up soon. Like I usually do when I write I just kinda let my mind wonder and this is where it took me. Hey it didn't turn out half bad.**

 ***Funny looks from everyone***

 **Fine, it did but still it's a pretty long chapter. I haven't been writing much recently so you people deserve it.**

 **WarriorOfHades Out!**


	8. Chapter 8

**Author's Note: Nin hao! I have basically been sick all day. Yeah it's just bunches of fun and rainbows. I have done nothing all day but read fanfiction and write it. Anywho here's the next chapter. Might not be the best seeing as I'm about to throw up.**

Magnus had just enough time to see the flash in her eyes before seventy plus years of battle instincts kicked in. She met Alec halfway across the room in seconds. Magnus had always thought of Nephilim as the most graceful creatures he had ever seen, more graceful than even vampires.

He was wrong.

She seemed to know what Alec was doing even before he himself didn't so much as walk or lunge as she did float towards him. Alec lasted a total of five seconds before he hit the floor. Alec's eyes turned towards Magnus and Magnus's name formed on his lips. Her stygian sword moved towards his throat with incredible speed.

"Stop, please."shouted Magnus. The sword stopped just before it pierced the skin of his throat. Both of them breathed hard as they stared at Magnus. Or rather as Alec stared at Magnus. Katherine knew better than to get detracted. Slowly, she moved the sword away from his throat and stepped back. Magnus rushed over and gathered a stunned Alec into his arms.

"Oh baby are you okay? I thought I lost you Alec, oh gods above what possessed you to do that? I thought for sure that she was gonna kill you. You stupid, stupid Nephilim. How-"he continued on this way whispering in Alec's ear. Katherine was obviously getting annoyed though.

"As touching as this little scene is, I'm afraid I'll have to interrupt. This little mishap has caused a little change in plans. Magnus, I'm aware that you have connections with Raphael Santiago. Tell Jace to go have a little conversation with him. The big step is coming,but this section of my plan must be taken slowly. As for your lover," she gestured at Alec." He will have my protection. You love him dearly enough to face my wrath. That is something not many can say. And this is for you." She tossed two small pins at his feet. "One is for your...charming...Nephilim the other is for Jace. Be sure they get to their respected persons." She turned away and the shadows darkened around her. Hellfire flashed and she was gone. Alec looked up at Magnus's tear stained face.

"Who the Hell was that?"

 **Author's Note: Sorry about this one. It's not the best because my sister is babysitting. AKA she is getting paid while I watch the kid. Fun. I might get the other up today but no promises.**

 **WarriorOfHades Out!**


	9. Chapter 9

**Author's Note:** **Здравствуйте! Here's the next chapter. As it turns out Nico knows Katherine. Or, at least, who she used to be. I am sooo bored over here. Like seriously bored. My friend Ruthy is being an amazing brat and I love her for it. On with the story!**

"Nico, do you really have to go?" pleaded Will as Nico packed.

"Yes Will I do. It will only be for a little while and I'll be back soon. Don't worry so much." He replied for the umpteenth time. He needed to leave and soon. He knew his father had planned for this to happen but so soon? So soon after the incident with Gaea? He needed to discuss this with his father.

"Nico please, do you have to leave so soon ?Couldn't you stay just a little longer? We met a guy with a few tattoos, so what? Nico please-" Nico had had enough. He spun around and placed his lips roughly against Will's. Will'slips were soft like silk and tasted like sunshine. He pulled away.

"I have to go Will. Don't worry I'll be fine." He started to slip into shadows.

"Nico wait!" he felt Will's hand grab his arm just as he descended into shadows.

Something was wrong. He was trying to guide the shadows, but they kept pulling him in a different direction. He felt another sharp tug and was jerked back into reality, however it was not where he expected to be. He tumbled onto a sidewalk with Will sprawled on top of him. Before Nico could say anything, Will jumped off of him and threw up into the canal beside him.

Wait a second... canal?

He stood and slowly scanned his surroundings. The cobblestone streets and canal water shone in the moonlight. He swallowed and forced himself not to join Will by the canal. He knew this street. Hell he grew up on this street. There were no lights on save for one small shop. His hands shook. He hadn't thought about _that_ shop in years. Will stumbled over to him and used his shoulder to support himself.

"Neeks? Where are we? And what the hell happened?"Will asks. Nico had to wait a moment before answering so his voice wouldn't shake.

"I don't know. Someone brought us here."

"Where's here?" he asks.

"Welcome to Venice, Italy." Nico points to the shop."Someone's expecting us."

 **Author's Note: Probably put the next chapter up today as well. I hate leaving cliff-hangers unresolved. That, and I literally have nothing else to do today.**

 **WarriorOfHades Out!**


	10. Chapter 10

**Author's Note: Hey people! A little blast from the past for Nico here. And I'm not trying to make Will seem inferior to Nico. But face it, Nico is a swordsman and Will is a healer. Not a lot of healers put too much stock into hero training. Will's badassness is just different from Nico's.**

Will was hesitant to follow Nico.

It might sound like he was being a bad boyfriend but honestly anything that had Nico di Angelo shaking was not something he wanted to meet. Nico was making his way towards the little shop, the only one with it's lights on. As they got closer, Will realized it was a bakery. Will prided himself as one of the few people who knew about Nico's past(what little he remembered that is)and was surprised that Nico had never told him anything like this. Nico had never said anything about a bakery or those who worked there. Nico seemed to gather himself at the door, taking a deep breath, and pushed it open.

A bell rang as they stepped in and they were bathed in soft golden light. Nico immediately drew his sword. Will felt extremely unprepared and vulnerable. He was a healer for the gods sake! He didn't carry a sword!

"So, uh, you knew the baker I'm guessing?" Will asks trying to lighten the mood. Nico swallowed.

"Not well. More like I knew his daughter. Her and Bianca used to be good friends. She treated me like her little brother. But she's supposed to be dead, reborn into a new life. This place has been abandoned for years."

"Doesn't look so abandoned to me." And it didn't. The soft candle light emitted from beautiful sconces on the walls, the old fashioned oven was burning brightly, and the smell of fresh baked sweets filled the air. There was soft clattering in the kitchen. Will strained to see through the glass-less window, through which the burning stove could be seen. Nico took a deep breath and seemed to relax. He stalked confidently towards the kitchen. Will stood dumbfounded by this sudden change. Cautiously, he followed after him. Nico placed one hand on the counter and jumped over it with ease leaving Will to clamber over it. Where Nico was a lithe, graceful panther, Will was a stumbling kitten, having trouble just getting his legs under him.

As they approached the kitchen, a soft melody carried through the air. Someone was singing. The melody was soft, sweet, and in a language Will could not understand. After a moment of listening, he realized it was Italian. He never learned the language, but Nico had a habit of cursing and ranting in the foreign tounge. Slowly they rounded the corner and stepped through an opened doorway. A girl, about 15 or 16, stood with her back towards them. Once she heard their entrance she stopped singing. She turned to face them and, in the space of a second, Nico had the tip of his sword resting against the hallow of her throat. He gasped, and Will skittered back a few feet. Her eyes were cold, the black irises matching the pupil. She wasn't staring at him though. She was staring at Nico.

"Katherine?" he said. His voice seemed shaky.

"Hello Niki." she said softly."Long time no see."

 **Author's Note: Ok I feel like this wasn't my best chapter. I know I'm dragging this meeting out waaay too long, but the next one should answer some questions about Katherine's past. Bear with me for a little while.**


	11. Chapter 11

**Author's Note: This chapter will be mostly flashback. Sorry it's been so long. Stupid people will be the death of me, but I'm still here so you people have to put up with me a little longer. ;)**

Katherine didn't want to explain. She wanted Nico to just magically understand what had happened. But she knew that was impossible. Slowly she told him.

 _She stared at Nico and Bianca. Nico was crying and she hated when he was sad. She never wanted to leave Venice, but Zues was making death threats again. This time though, it seemed he could follow through. His orders to her father were to surrender all his children to Camp Half-Blood. Sadly his children were even more stubborn then he was. She and her siblings had absolutely refused to go. Why should they when neither they nor their father had ever been recognized or honored there? Her siblings were currently gathering in the Underworld. She had fought tooth and nail for him to bring Nico and B but no dice. Nico clung to her dress._

 _"Please Kat don't go! I'll miss you." he cried. Bianca stood apart from them, her face oddly solemn. She knelt and carefully pried Nico's hands from her dress._

 _"It's ok Nikki. I'll see you again."_

 _"Wait, take this." Nico handed her a little silver locket. Inside was a picture of her, Nico, and B in one side and Maria, her mother Isabelle, and her step-father Raphael. She snapped it shut, nodded once to her mother and step-father, and left them, and Venice, behind her._

Katherine pulled the locket off her neck and pressed it into Nico's palm. Nico stared at it for a moment before pointing out the single flaw.

"It's dented."

 _Katherine charged into battle beside her troops. Guns and/or bullets had been banned by popular vote. She heard screams and battle cries dully in her ears. She took enemies down left and right. She never checked to see if they were dead. If you fought against her you were dead, simple and easy. She took down eight without so much as batting an eye. There were about 40 Children of The Sky and 32 wind spirits, and The Sea's Children had dropped out of the war after year one when they realized, like she had, that Zues was completely nuts. Suddenly a dagger was thrust at her chest. There was a soft clang as the demigod's dagger collided with her locket. Her vision went red. She left him with a slit throat, bleeding out on the battlefield._

"Where have you been?" asked Nico.

 _"Katherine di Luminoso, because your father had pleaded on your behalf your punishment will be light. You are here by sentenced by the Olympian Council to an unknown immortality. The world is forbidden from knowing your presence. You will be the priestess of the Necromanteion. You will serve three deadly quests in Tartarus, and you shall complete whatever quest any of the other gods have prepared for you. You will not be released until I otherwise say so. Do you swear to abide by these terms as the other option is an afterlife in Tartarus?" asked Zues. Katherine looked up, her face smeared in blood and ash from single-handedly carrying all 27 of her sibling to their funeral pyres after killing their murderers. The final 23 children of Zues had massacred her siblings during a party for her brother's birthday. She had challenged them to one-on-one duels and she had won. She spoke coldly._

 _"I swear on the River Styx._

Nico's expression was blank. Then he slowly pressed the locket back into her hands.

"It's good to have you back...Kitty."

Author's Note: Nico just called the Shadow's Assasian Kitty...Anyway the next chapter will get back to the actual, you know, plot.

...Yes there is a plot.

WarriorOfHades Out!


	12. Chapter 12

**Author's Note: Hey people! FYI next chapter will not be an update! I am extremely superstitious . However when thirteen is put up fourteen will be as well. Call me childish but hey, everyone has at least one superstition. On to the story.**

Jace walked slowly up to the entrance to the Dumort, fingering the pin Magnus had given him. He tossed a nervous glance towards Alec, who seemed completely at ease despite where they were headed. He hadn't wanted Alec to come( and frankly neither had Magnus) but Alec had insisted. They walked in silence, Jace was nervous as fuck but Alec was calm and collected. Then again, that was just how Alec was. Unlike Jace, Alec didn't need humor, sarcasm, snarky remarks, or anything else to seem in control. He was always cool and calm in the face of danger. He could risk his life for him or Izzy and not bat an eye and then slip quietly into the background again like it was nothing. Alec was always overshadowed even when he didn't deserve it. Suddenly Alec spoke.

"What's wrong?"

"Huh?" said Jace.

"You look frustrated and confused. What's on your mind?" He said like he was asking the weather or the time.

"How are you so calm about this? We're headed on a mission to a vampire lair for some psychotic goth girl and you act like we're just running to Taki's." Jace fumed.

"You think I'm not freaking the fuck out? Were you or were you not listening when I told you she stuck a sword at my throat? She has reasons to be the way she is. As for being calm, it's kind of my job. I'm the stable big brother remember." Alec said. Jace ignored the last part.

" Reasons? What reasons? How am I her 'champion' but you know more than I do?" Alec sighed.

"You're like a pawn. She just needs you to perform a job. Albeit not a fun one, but it shouldn't kill you."

"You know her plan?"

"Not really. Just that she has one."

Jace didn't get to answer. They stared open-mouthed at the door, which was clean, polished, and, most importantly, no longer boarded up. A vampire opened it from the other side and nodded their entrance. If the door was a change the inside was a complete remodel. The carpets were clean, the walls repainted, the stairs and furniture rebuilt. Soft golden light spilled from a candle-lit chandelier and classic music played softly.

"This way." The vampire hissed. He led them into what looked like a throne room. Sitting on the thrones were none other than the dark haired boy Nico and his(assumed) boyfriend...Bill?...no Will. Nico regarded him coldly. Then he called out.

"Katherine! Your champion is here. Oh, and he's brought a friend." The boy next to him Will put a hand on his. Nico looked at him and his eyes softened. The moment didn't last long. With a flash of black Hellfire the shadows darkened in one corner and di Luminoso appeared.

"Thank you Nico. I had a few things to finish up." she said as she stalked across the room. She took the seat next to Nico. "Welcome Jace and Alec Lightwood." He opened his mouth to correct her and then snapped it shut again. He wasn't that stupid. "I believe it is time to explain a few things. This is my brother Nico di Angelo and his boyfriend Will Solace." her eyes flashed. "How much do you know about Greek mythology?"

 **Author's Note: Here it is. So we don't have to go through the whole explaining things, I'll fast forward to the next day when chapter fourteen is out. There shouldn't be any break-up/crossover ships for Katherine. I have big plans for Katherine's love life, which will play into her past. I hope you enjoyed it. Also Katherine is not completely heartless, that's just a cover from her acquaintance's POV. She might be a crazy bitch but she's not a heartless bitch.**

 **WarriorOfHades Out!**


	13. Chapter 13

**Author's Note: This review was posted a few days ago. While constructive criticism is**

 **appreciated, I need to get something straight. I don't wish to be all powerful. I don't**

 **want to be mysterious or beautiful. I want to write. I want to create something new.**

 **I write because I want to write, not because others want me to write. In all honesty**

 **I probably am childish and cliche, but I don't care. I don't want to be my characters**

 **I just want to create them.**

 **JustACasualReadr chapter 12 . Sep 28**

 **wooowww...Mary-Sue much? Its cool that you wish to be this all powerful, mysterious,**

 **beautiful person, but don't you think its quite childish and cliche to use it as a character?**

 **And... It's the 13th chapter so this won't be an update. Sorry for not getting a chapter up**

 **for so long. With any luck I'll get another one up tomorrow. So sorry about all this I've**

 **been so busy lately.**

 **WarriorOfHades Out!**


	14. Chapter 14

**Author's Note: Hey guys! Up with a new chapter! I know I said I would get it to you yesterday but my sister had to go to the hospital. Turned out to be nothing but I didn't get home until two in the morning. I'm so so sorry! Anyway here's the next update!**

Jace woke up in an unfamiliar bed groggy and disoriented. The source of his rude awakening resounding through the Hotel Dumort again. A blood-curdling scream that echoed off the walls, causing the shadows to leap up at him. He toppled out of bed and ran towards the door. The shadows grew becoming cold and tangible pushing him away from the center of the dark storm. He pushed past them only to find the door locked. He slammed his shoulder against it. It shuddered, a tremor passed through the shadows. They pulled at him jerking him away from the door. He threw himself at it again and it gave way with an almighty crack. He wished he had left it closed.

Katherine lay on the bed her body convulsing and shaking in such a violent an unnatural way that it made him want to hurl. He mouth opened wider and another inhuman screech resounded across the room. Nico burst through the door. The shadows didn't pull him away, but rather pushed him on.

"Rosy no! I'm sorry, I'm so sorry, please, please, please!" She screeched. Nico ran up to the bed Will hot on his heels.

"Kat wake up! Come on Kat it's just a dream. Come on!" he said. Suddenly Katherine became very still. The shadows stilled as well and disappeared as she sat bolt upright, eyes flying open.

"Wha-? Nikki, Will?" she asked.

"You had a nightmare Kat. You were screaming your head off." said Nico looking at her calm expression in utter disbelief.

"I-I did? Oh, I guess I did. Don't worry about it Nikki."

"Don't worry about?! You scared the vampires Kat! There were shadows everywhere!" he all but shouted. She looked frustrated, gripping the bridge of her nose eyes closed.

"Nikki was I shouting names?" she asked. He blinked before answering.

"Yeah actually you were. Someone named...Rosy?" She winced at the name.

"Nikki do me a huge favor and never, _ever,_ ask who that is, okay? Please? It's tied to a lot a bad memories that need to stay in the the dark, dank, snake pit where it was buried alive decades ago." Will, Nico and Jace blinked again.

"You certainly paint a very vivid word picture." said Jace. They all stared at him, obviously having forgotten he was there. "Breakfast?" he suggested. Will and Nico were supporting incredulous looks where as Katherine look relieved.

"That sounds like a great idea." she said.

"If you don't mind me asking General, why are we visiting Magnus an Alec on Magnus's day off?" he asks nervously. They were currently walking towards Magnus's flat and honestly, if anything Magnus says to tease him is true, he did _not_ want to see what was going on.

"You act as if you didn't know they were having sex." says Nico flippantly. Jace went a whole new shade of red.

"Why are we walking?" he asks instead of answering Nico.

"Shadow travel is fast, but I haven't had the pleasure of actually walking for literal decades." she said. And it was true she seemed to be enjoying herself. She wasn't smiling. She never did. But she looked amused and even content. Jace let the questions go for now. They stopped in front of the the building. She walked right into the building and up the stairs. The closer they got the louder the cries seemed to get.

"Dammit Alec stop teasing!" said Magnus loudly. Jace covered his ears and Will's face was as red as a tomato. The only words said after that was mindless begging from Magnus and the occasional dirty talk from Alec. When the noises finally ceased, Katherine opened the door. Alec and Magnus were laying on the couch in a spooning position, Alec being the big spoon. He was whispering sweet nothings into Magnus's ear as he played with his hair. Jace counted his blessing that they were covered with a blanket, knowing his face was probably as pale as a sheet. Katherine spoke up.

"If you're finished, I need to speak to Magnus."

 **Author's Note: Yes, no? I didn't want Katherine to seem like invincible. She is still mortal and she has her own fucked up past. People have been asking for smut scenes and I'm not sure if I'm comfortable with writing that. I'll think on it though. Maybe another chapter today? If I get the chance.**


	15. Chapter 15

**Author's Note: Hey guys! Sorry it's been so long since my last update! Haven't been feeling to good lately and with writers block? Yeah chapters will be coming slowly. Anywho, enjoy.  
**

"So you're Nico di Angelo?" asks Magnus staring at said son of Hades with wide eyes." _The_ son of Hades who traveled through Tartarus _alone_?"

Nico looked extremely uncomfortable at being asked so many questions, especially those of that particular nature. Will looked, like Alec, to be on the verge of laughing. Alec at Magnus's strange child-like interest, Will at Nico's incredulous reactions to some of the questions.

"My father does _not_ have flaming hair. Let alone _blue_ flaming hair." says Nico wrinkling his nose. Jace was sitting on the floor playing with Chairman Meow. The Chairman batted at Jace's golden hair getting more and more frustrated with his short stature. Katherine sat on the sofa, a glass of scotch in her hand. The absurdity of the situation was lost to it's comfort. Two Shadowhunters, a warlock, three demigods, and a cat. Suddenly, a zombie appeared dressed in a butler's uniform and holding a tray with a bottle of scotch and a bowl of what looked like pomegranate seeds covered in crystallized sugar. She took the bowl as the zombie refilled her scotch and then, with a bow, disappeared. They stared at her as she sipped her scotch and tossed a few of the seeds in her mouth.

"As I was saying Magnus," she said as though nothing had happened."We need a party, one you don't mind being crashed of course. And of course we need a few monsters, which I can provide easily."

"You want me to throw a party so it can be crashed by monsters you've summoned all so there's a reason for a few demigods to show up?"

"Unless you think it would be a better idea to invite them to Camp Half-Blood? Camp Jupiter? New Rome? Or, better yet, let's just invite a few demigods to visit the Clave." She said sarcasm dripping heavily. Magnus flinched. Nico eyed her strangely along with Alec.

"Kat? Are you drunk?" asked Nico. She was being a friendly and sarcastic. Or as friendly as she really got anymore.

"Drunk? No. Maybe a slight buzz."

"Just a buzz?"

" I swear Nikki. I haven't got drunk off my ass in 15 years." Alec looked impressed. Then he asked a totally un-Alec-like question.

"How long has it been since you've been laid?" They all stared at him before Magnus burst out laughing. Katherine wasn't even fazed.

"'Bout seventy years give or take." Suddenly Jace looked very pale.

"Can we not get into each other's sex lives considering what we just walked in on not an hour ago." he pleaded.

"Not our fault you're such a nosy little bastard." said Alec. Jace got a mischievous gleam in his eyes.

"Still never would have thought of Magnus as a bottom."

Now it was Alec's turn to laugh.

 **Author's Note:Should have another one up tomorrow. Also I literally have a pinterest account for nothing but looking at fanart for my OTP.**

 **WarriorOfHades Out!**


	16. Chapter 16

**Author's Note: Gods guys sorry! I seriously thought about abandoning this story for a while be cause I couldn't think of what to write next. My writer's "block" felt more like a fucking mountain. So sorry! A new chapter is in the works and if it's not up later today it will be up by tomorrow I swear on the Styx. Again sorry guys**


	17. Chapter 17

**Author's Note: Hey guys I know it's a little late but I swore on the Styx. Here it is!**

Percy frowned at the letter in his hand. The rest of the Seven crowded around him as he read it aloud for the third time in a row.

 _Seven,_

 _You are hereby cordially invited to attend a party tonight courtesy of Magnus "Magnificent" Bane. The party will of course be held at the following address. We sincerely hope you will be in attendance._

 _Yours Truly_

 _-Magnus Bane and Co._

"A party?" asked Frank,not for the first time. "And who's Magnus?" Hazel looked thoughtful for a moment.

"Magnus...Magnus... I'm not sure but the name sounds familiar." she said. "Well are we going or not?" They looked at her as though she were crazy. But she didn't look embarrassed. She looked almost...sad?

"I mean I was just thinking how Leo would have jumped for it. He would have been so excited even if it was a trap." she said. They paused in thought. They could all see it clearly, Leo jumping around excitedly making some cheesy joke and convincing them all to go, that it would be fun, an adventure.

"Well I'm curious. For Leo?" Percy said. The Seven looked at each other.

"For Leo." they said.


End file.
